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A Biobank of Breast Cancer Explants with Preserved Intra-tumor Heterogeneity to Screen Anticancer Compounds

View Article: PubMed Central - PubMed

ABSTRACT

The inter- and intra-tumor heterogeneity of breast cancer needs to be adequately captured in pre-clinical models. We have created a large collection of breast cancer patient-derived tumor xenografts (PDTXs), in which the morphological and molecular characteristics of the originating tumor are preserved through passaging in the mouse. An integrated platform combining in vivo maintenance of these PDTXs along with short-term cultures of PDTX-derived tumor cells (PDTCs) was optimized. Remarkably, the intra-tumor genomic clonal architecture present in the originating breast cancers was mostly preserved upon serial passaging in xenografts and in short-term cultured PDTCs. We assessed drug responses in PDTCs on a high-throughput platform and validated several ex vivo responses in vivo. The biobank represents a powerful resource for pre-clinical breast cancer pharmacogenomic studies (http://caldaslab.cruk.cam.ac.uk/bcape), including identification of biomarkers of response or resistance.

No MeSH data available.


Related in: MedlinePlus

Related to Figure 4 and STAR Methods(A) AUC and iC50 values (as percentage, see STAR Methods) for the EGFR/ERBB2 inhibitor BIBW2992 (Afatinib). Dots represent estimates using all technical replicates and error bars are standard errors of the estimates obtained using each technical replicate individually.(B) BRCA1 promoter methylation percentage measured by RRBS (n = 33 models).(C) BRCA1 expression measured by expression microarrays (n = 35 samples from 19 models).
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figs6: Related to Figure 4 and STAR Methods(A) AUC and iC50 values (as percentage, see STAR Methods) for the EGFR/ERBB2 inhibitor BIBW2992 (Afatinib). Dots represent estimates using all technical replicates and error bars are standard errors of the estimates obtained using each technical replicate individually.(B) BRCA1 promoter methylation percentage measured by RRBS (n = 33 models).(C) BRCA1 expression measured by expression microarrays (n = 35 samples from 19 models).

Mentions: Third, we explored whether the combined analysis of PDTC drug responses and molecular data recapitulated known mechanisms of drug sensitivity and resistance. For example, sensitivity to the EGFR/ERBB2 inhibitor BIBW2992 (afatinib) was seen in two of the three Her2+ models tested (Figure S6A). Sensitivity to PARP inhibition (Drew et al., 2011) was seen in a model with somatic BRCA1 promoter methylation and consequent lack of expression (STG201) and in a model from a patient with a germline-truncating BRCA1 mutation (VHIO124; Figures S6B and S6C; Table S6, and Figure 6 for ex vivo and in vivo data, respectively). Interestingly, two models from BRCA1 germline mutation carriers were resistant to PARP inhibitors, and these had inactivating mutations of 53BP1 (STG316: c.134+3A > C) and MAD2L2 (VHIO179: c.66_67delAG; Table S6; Figure 6). Resistance to PARP inhibitors due to loss of non-homologous end-joining (NHEJ) has been previously reported for both 53BP1 (Bouwman et al., 2010, Bunting et al., 2010, Chapman et al., 2012) and MAD2L2 (Boersma et al., 2015, Xu et al., 2015). These data therefore further demonstrate breast cancer explants recapitulate known mechanisms of both drug sensitivity and resistance.


A Biobank of Breast Cancer Explants with Preserved Intra-tumor Heterogeneity to Screen Anticancer Compounds
Related to Figure 4 and STAR Methods(A) AUC and iC50 values (as percentage, see STAR Methods) for the EGFR/ERBB2 inhibitor BIBW2992 (Afatinib). Dots represent estimates using all technical replicates and error bars are standard errors of the estimates obtained using each technical replicate individually.(B) BRCA1 promoter methylation percentage measured by RRBS (n = 33 models).(C) BRCA1 expression measured by expression microarrays (n = 35 samples from 19 models).
© Copyright Policy - CC BY
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5037319&req=5

figs6: Related to Figure 4 and STAR Methods(A) AUC and iC50 values (as percentage, see STAR Methods) for the EGFR/ERBB2 inhibitor BIBW2992 (Afatinib). Dots represent estimates using all technical replicates and error bars are standard errors of the estimates obtained using each technical replicate individually.(B) BRCA1 promoter methylation percentage measured by RRBS (n = 33 models).(C) BRCA1 expression measured by expression microarrays (n = 35 samples from 19 models).
Mentions: Third, we explored whether the combined analysis of PDTC drug responses and molecular data recapitulated known mechanisms of drug sensitivity and resistance. For example, sensitivity to the EGFR/ERBB2 inhibitor BIBW2992 (afatinib) was seen in two of the three Her2+ models tested (Figure S6A). Sensitivity to PARP inhibition (Drew et al., 2011) was seen in a model with somatic BRCA1 promoter methylation and consequent lack of expression (STG201) and in a model from a patient with a germline-truncating BRCA1 mutation (VHIO124; Figures S6B and S6C; Table S6, and Figure 6 for ex vivo and in vivo data, respectively). Interestingly, two models from BRCA1 germline mutation carriers were resistant to PARP inhibitors, and these had inactivating mutations of 53BP1 (STG316: c.134+3A > C) and MAD2L2 (VHIO179: c.66_67delAG; Table S6; Figure 6). Resistance to PARP inhibitors due to loss of non-homologous end-joining (NHEJ) has been previously reported for both 53BP1 (Bouwman et al., 2010, Bunting et al., 2010, Chapman et al., 2012) and MAD2L2 (Boersma et al., 2015, Xu et al., 2015). These data therefore further demonstrate breast cancer explants recapitulate known mechanisms of both drug sensitivity and resistance.

View Article: PubMed Central - PubMed

ABSTRACT

The inter- and intra-tumor heterogeneity of breast cancer needs to be adequately captured in pre-clinical models. We have created a large collection of breast cancer patient-derived tumor xenografts (PDTXs), in which the morphological and molecular characteristics of the originating tumor are preserved through passaging in the mouse. An integrated platform combining in vivo maintenance of these PDTXs along with short-term cultures of PDTX-derived tumor cells (PDTCs) was optimized. Remarkably, the intra-tumor genomic clonal architecture present in the originating breast cancers was mostly preserved upon serial passaging in xenografts and in short-term cultured PDTCs. We assessed drug responses in PDTCs on a high-throughput platform and validated several ex vivo responses in vivo. The biobank represents a powerful resource for pre-clinical breast cancer pharmacogenomic studies (http://caldaslab.cruk.cam.ac.uk/bcape), including identification of biomarkers of response or resistance.

No MeSH data available.


Related in: MedlinePlus